Hi, and welcome to the forum.

Your chances of finding work will vary directly with your fluency in the language. The better you speak French, the better chance you'll have. Estate agents work quite a bit differently here than in the UK, due to the rather different laws regarding property transactions, so that might be a stretch (at least at first).

We seem to have lots of folks here lately who do "care work." I suppose it depends on exactly what you mean here. France has a number of programs in place whereby various forms of "care work" (as I understand the term) can be subsidized by the state - either through the health insurance scheme or via tax breaks. While it might be possible to find relevant jobs within the anglophone expat community in the south of France, most people are going to want care workers who qualify for the various state subsidy programs, which means either you will need to qualify under French law in the appropriate profession or will need to set up a French company to assure that VAT matters are properly handled. (In other words, not impossible, but start looking into the details as soon as you can.)

For finding a retail job, it will be your French ability more than anything else. It might not be a bad idea to make a couple exploratory trips to France to try to scout out the job market for yourself.

An excellent source for general information on the "administrative" side of life in France is the Service Public website here: SERVICE PUBLIC - Particuliers especially the sections on "Etrangers in France", "Emploi, travail", and "santé".
Cheers,
Bev